The present invention relates to a hard surface cleaning composition containing a positively charged surfactant-polymer complex.
This invention relates to an improved all-purpose liquid cleaner designed in particular for cleaning hard surfaces and which is effective in removing grease soil and/or bath soil and in leaving unrinsed surfaces with a shiny appearance.
In recent years all-purpose liquid detergents have become widely accepted for cleaning hard surfaces, e.g., painted woodwork and panels, tiled walls, wash bowls, bathtubs, linoleum or tile floors, washable wall paper, etc. Such all-purpose liquids comprise clear and opaque aqueous mixtures of water-soluble synthetic organic detergents and water-soluble detergent builder salts. In order to achieve comparable cleaning efficiency with granular or powdered all-purpose cleaning compositions, use of water-soluble inorganic phosphate builder salts was favored in the prior art all-purpose liquids. For example, such early phosphate-containing compositions are described in U.S. Pat. Nos. 2,560,839; 3,234,138; 3,350,319; and British Patent No. 1,223,739.
In view of the environmentalist""s efforts to reduce phosphate levels in ground water, improved all-purpose liquids containing reduced concentrations of inorganic phosphate builder salts or non-phosphate builder salts have appeared. A particularly useful self-opacified liquid of the latter type is described in U.S. Pat. No. 4,244,840.
However, these prior art all-purpose liquid detergents containing detergent builder salts or other equivalent tend to leave films, spots or streaks on cleaned unrinsed surfaces, particularly shiny surfaces. Thus, such liquids require thorough rinsing of the cleaned surfaces which is a time-consuming chore for the user.
In order to overcome the foregoing disadvantage of the prior art all-purpose liquid, U.S. Pat. No. 4,017,409 teaches that a mixture of paraffin sulfonate and a reduced concentration of inorganic phosphate builder salt should be employed. However, such compositions are not completely acceptable from an environmental point of view based upon the phosphate content. On the other hand, another alternative to achieving phosphate-free all-purpose liquids has been to use a major proportion of a mixture of anionic and nonionic detergents with minor amounts of glycol ether solvent and organic amine as shown in U.S. Pat. No. 3,935,130. Again, this approach has not been completely satisfactory and the high levels of organic detergents necessary to achieve cleaning cause foaming which, in turn, leads to the need for thorough rinsing which has been found to be undesirable to today""s consumers.
Another approach to formulating hard surfaced or all-purpose liquid detergent composition where product homogeneity and clarity are important considerations involves the formation of oil-in-water (o/w) microemulsions which contain one or more surface-active detergent compounds, a water-immiscible solvent (typically a hydrocarbon solvent), water and a xe2x80x9ccosurfactantxe2x80x9d compound which provides product stability. By definition, an o/w microemulsion is a spontaneously forming colloidal dispersion of xe2x80x9coilxe2x80x9d phase particles having a particle size in the range of 25 to 800 xc3x85 in a continuous aqueous phase.
In view of the extremely fine particle size of the dispersed oil phase particles, microemulsions are transparent to light and are clear and usually highly stable against phase separation.
Patent disclosures relating to use of grease-removal solvents in o/w microemulsions include, for example, European Patent Applications EP 0137615 and EP 0137616xe2x80x94Herbots et al; European Patent Application EP 0160762xe2x80x94Johnston et al; and U.S. Pat. No. 4,561,991xe2x80x94Herbots et al. Each of these patent disclosures also teaches using at least 5% by weight of grease-removal solvent.
It also is known from British Patent Application GB 2144763A to Herbots et al, published Mar. 13, 1985, that magnesium salts enhance grease-removal performance of organic grease-removal solvents, such as the terpenes, in o/w microemulsion liquid detergent compositions. The compositions of this invention described by Herbots et al. require at least 5% of the mixture of grease-removal solvent and magnesium salt and preferably at least 5% of solvent (which may be a mixture of water-immiscible non-polar solvent with a sparingly soluble slightly polar solvent) and at least 0.1% magnesium salt.
However, since the amount of water immiscible and sparingly soluble components which can be present in an o/w microemulsion, with low total active ingredients without impairing the stability of the microemulsion is rather limited (for example, up to 18% by weight of the aqueous phase), the presence of such high quantities of grease-removal solvent tend to reduce the total amount of greasy or oily soils which can be taken up by and into the microemulsion without causing phase separation.
The following representative prior art patents also relate to liquid detergent cleaning compositions in the form of o/w microemulsions: U.S. Pat. Nos. 4,472,291xe2x80x94Rosario; 4,540,448xe2x80x94Gauteer et al; 3,723,330xe2x80x94Sheflin; etc.
Liquid detergent compositions which include terpenes, such as d-limonene, or other grease-removal solvent, although not disclosed to be in the form of o/w microemulsions, are the subject matter of the following representative patent documents: European Patent Application 0080749; British Patent Specification 1,603,047; 4,414,128; and 4,540,505. For example, U.S. Pat. No. 4,414,128 broadly discloses an aqueous liquid detergent composition characterized by, by weight:
(a) from 1% to 20% of a synthetic anionic, nonionic, amphoteric or zwitterionic surfactant or mixture thereof;
(b) from 0.5% to 10% of a mono- or sesquiterpene or mixture thereof, at a weight ratio of (a):(b) being in the range of 5:1 to 1:3; and
(c) from 0.5% 10% of a polar solvent having a solubility in water at 15xc2x0 C. in the range of from 0.2% to 10%. Other ingredients present in the formulations disclosed in this patent include from 0.05% to 2% by weight of an alkali metal, ammonium or alkanolammonium soap of a C13-C24 fatty acid; a calcium sequestrant from 0.5% to 13% by weight; non-aqueous solvent, e.g., alcohols and glycol ethers, up to 10% by weight; and hydrotropes, e.g., urea, ethanolamines, salts of lower alkylaryl sulfonates, up to 10% by weight. All of the formulations shown in the Examples of this patent include relatively large amounts of detergent builder salts which are detrimental to surface shine.
A pH neutral microemulsion composition based on paraffin sulfonate and ethoxylated nonionic surfactant is able to deliver improved grease cleaning versus built, alkaline compositions. Besides the improved grease cleaning, this approach is much safer to surfaces as well as less aggressive on consumer""s hands (Loth et alxe2x80x94U.S. Pat. No. 5,075,026).
The microemulsion technology provides outstanding oil uptake capacity because of the adjustment of the curvature of the surfactant micelles by the molecules of the cosurfactant. Rod-like micelles are preferred as they can xe2x80x9cswallowxe2x80x9d oil to become globular without increasing the surface of contact between the hydrophobic core of the micelle and the hydrophilic continuous phase.
In diluted usage however, the microemulsion state is usually lost and the cleaning performance relies on the adsorption efficacy and leaving character of the surfactant system. Nonionic surfactants perform very well on grease, as they are excellent grease xe2x80x9csolubilizersxe2x80x9d. Actually, they spontaneously form swollen micelles. In moderate climate countries such as the northern states of the United States and the northern countries of Europe, the soil on the hard surfaces contains a major proportion of greasy materials. It is accordingly not surprising that the anionic-nonionic surfactant based microemulsion is so very efficient in those countries. However, nonionic surfactants do not impart oil repelling properties and can not deliver soil antiattachment properties on treated hard surfaces so as to achieve next time easier cleaning of said treated surface.
The instant invention teaches hard surface cleaning containing a positively charged complex of an anionic surfactant which is an alkali metal salt such as sodium of a fluoroalkyl sulfonate, or an ammonium salt of a fluoroalkyl sulfonate, or a mixture thereof, which exhibits very low surface tensions with a polycationic polymer that imparts oil repelling properties and delivers soil antiattachment properties on treated hard surfaces and delivers this desired property.
The present invention provides an improved, clear, liquid hard surface cleaning composition having improved interfacial tension which improves cleaning hard surfaces such as plastic, vitreous and metal surfaces having a shiny finish, oil stained floors, automotive engines and other engines. More particularly, the improved cleaning compositions exhibit good grease soil removal properties and leave the cleaned surfaces shiny without the need of or requiring only minimal additional rinsing or wiping. The latter characteristic is evidenced by little or no visible residues on the unrinsed cleaned surfaces and, accordingly, overcomes one of the disadvantages of prior art products. The instant compositions exhibit a grease release effect in that the instant compositions impede or decrease the anchoring of greasy soil on surfaces that have been cleaned with the instant compositions as compared to surfaces cleaned with a microemulsion composition which means that the grease soiled surface is easier to clean upon subsequent cleanings.
Surprisingly, these desirable results are accomplished even in the absence of polyphosphate or other inorganic or organic detergent builder salts and also in the complete absence or substantially complete absence of grease-removal solvent.
The invention generally provides a stable, clear all-purpose, hard surface cleaning composition especially effective in the removal of oily and greasy oil. The cleaning composition includes, on a weight basis:
about 0.1% to about 20%, more preferably about 0.2% to about 15% of a positively charged complex comprising at least one alkali metal salt of a fluoroalkyl sulfonate surfactant or at least one ammonium salt of a fluoroalkyl sulfonate surfactant or mixtures thereof, and a polycationic polymer;
about 0 to about 25%, more preferably 1% to 20%, of a water-mixable cosurfactant having either limited ability or substantially no ability to dissolve oily or greasy soil;
0 to about 1.5% of a fatty acid;
0 to about 5% of magnesium sulfate heptahydrate;
about 0 to about 5.0% of a perfume or water insoluble hydrocarbon; and
the balance being water, said proportions being based upon the total weight of the composition.
The cleaning composition can be in the form of a microemulsion in which case the concentration of the water mixable cosurfactant is about 0 to about 25 wt. %, preferably about 1 wt. % to about 20 wt. % and the concentration of the perfume or water insoluble hydrocarbon is about 0.4 wt. % to about 5.0 wt. %. The dispersed oil phase of the o/w microemulsion is composed essentially of a water-immiscible or hardly water-soluble perfume.
The present invention relates to a stable all purpose hard surface cleaning or microemulsion composition containing a surfactant-polymer complex for delivering soil antiattachment properties. The invention also relates to a light duty liquid composition or light duty liquid microemulsion composition. This present invention also useful in the formation of toilet bowl cleaners.